There is an interest in detecting inflammations in the human body without invasively inspecting the body.
Most known methods and devices are complicated and expensive.
Hence, an improved device and method would be advantageous and in particular allowing for increased flexibility, cost-effectiveness, non-invasiveness and user friendliness would be advantageous.
WO 03/093803, and corresponding U.S. Ser. No. 10/979,082 of same applicant disclose a method and device for investigation of a surface layer (e.g. paint) of a material, wherein a penetration of a gas into the material through the surface layer is measured. The measurement of the passage of said gas into the material is performed by a method comprising measurement of light absorption by said gas by absorption spectroscopy. However, this method and device are not provided for medical purposes according to the disclosure. U.S. Ser. No. 10/979,082 is herein incorporated by reference in its entirety.
U.S. Pat. No. 3,674,008 discloses an instrument which quantitatively measures optical density of the transilluminated body portion. The instrument comprises a controllable, relatively low-frequency oscillator generating pulses which are applied to a light source through a first expand and delay circuit. A light conducting means, optically couples the light source to one side of the body portion and a similar means optically couples another side of the body portion to a light detector. After compensation for ambient light, the output of the detector is coupled to a sample and a hold circuit that is triggered by the controllable oscillator through a second expand and delay circuit. The stored signal in the sample and hold signal is proportional to transmittance and is converted to a visual indication of optical density by a calibrated display means. However, U.S. Pat. No. 3,674,008 fails to disclose the measurement of free gas in body cavities, since the instrument only relies on the fact that fluids lead light better than opaque material, thus being able to detect light travelling in fluid light conducting paths.
U.S. Pat. No. 5,706,821 discloses a spectrometric technique for quantitatively determining the change in concentration of a substance which is contained in a medium which both absorbs and scatters spectroscopically interrogated radiation. The medium includes a plurality of such regions displaying potentially different absorption and scattering properties to the radiation. Specific applications are disclosed involving the noninvasive determination of changes in concentration of the substances oxyhemoglobin and deoxyhemoglobin and/or changes in the redox state of the substance cytochrome oxidase within the brain or skeletal muscle. However, U.S. Pat. No. 5,706,821 fails to disclose the change of concentration of an unbound gas by measuring the gas in itself. The only technique for quantitatively determining the change in concentration is through an intermediate, i.e. oxyhemoglobin and/or deoxyhemoglobin.
EP 0801297 discloses a method of projecting measuring light to a measurement portion of an object with high reproducibility so as to always establish a constant measuring condition. An optical measuring apparatus is disclosed in EP 0801297 that includes a spectral analysis portion for detecting a spectral intensity of reflected light of measuring light projected to the hand of a subject. When the measurement portion of the hand is registered, an image of the palm of the hand is taken by a CCD camera, and an operator selects a portion having characteristics features from the pattern of the image so taken. When spectral analysis is executed, the palm of the hand is again imaged by the CCD camera, the portion at the time of registration is detected from the pattern of that image, and after the spectral analysis portion is moved by a movement mechanism, and measuring light is allowed to be incident on the characteristic feature portion so registered. However, EP 0801297 fails to disclose the measurement of free gas in body cavities.